The summer months are a busy time for any producer, and poultry is no exception.
Like any pet, wild or production animal heat has an impact on their health.
The heat even effects the poultry – even indoors.
The Heat: Heat is a factor to stressful conditions for birds, but humidity is just as important.
“Many times we focus on keeping the birds cool during the hottest part of the day, but a very stressful time is when the sun goes down and it starts to cool off. This is when the humidity will spike up and can reach 80 to 100 percent because the cooler air can’t hold as much moisture as warmer air,” said Susan Watkins, Distinguished Poultry Science Professor with University of Arkansas’ Division of Agriculture.
One source thermoregulation for birds is evaporation. Birds aid in the evaporation process by panting, moving the air quickly out of the bird’s lungs.
“Since birds must pant to get rid of excess heat, the humidity component is important because if the humidity is high, then it is hard for the birds to add the heat from their breath into the already saturated air,” she said.
Watkins said the poultry industry uses the number 160.
“When the temperature and humidity add up to 160, birds are experiencing stressful environmental conditions that can jeopardize their life,” Watkins said.
For larger birds, like market age broilers or breeders, temperatures reaching near 90 to 100 degrees can cause birds to experience stressful conditions.
The Problem: When it is hot outside, humans have a suppressed appetite and tend to eat less. The same instance happens with poultry when they put out a lot of effort to keep cool.
“If it does get really hot and they are spending a great deal of time panting, then the birds will not eat much and between the heat stress and depressed appetite, they can stop laying or more likely, experience a drop in egg production, particularly broiler breeders,” Watkins said.
For broilers, heat plays a major role in production as well. If the broilers are spending all their energy trying to stay cool, they will not gain weight.
“It takes a lot of energy to cool themselves and this will have a big impact on feed conversion because calories are going for cooling not growth,” Watkins said.
The Solution: What can producers do to help cool birds? Ventilation is a major role in commercial houses to keep the air flow going to cool the birds.
“The biggest things commercial poultry producers can do to minimize the impact of hot days is have adequate wind speed in tunnel ventilated houses,” Watkins said. “Make sure the houses are tight and well insulated so hot air does not leak in and make sure the cool cells are in good working condition.”
Watkins said cool cell maintenance is crucial for good air flow.
Cool cells that are clogged or have buildup reduce the cooling of the tunnel barn.
“As cool cells evaporate water, minerals concentrate in the recirculation tank and this can cause the pH of the water to increase,” Watkins said. “This rising pH is what makes if favorable for mineral build-up or the other extreme where the water virtually becomes lye soap and eats the resin out of the pads causing them to sag.” Sprinklers – in place of foggers – cause houses to be less humid and more comfortable for the birds and use less water than cool cells.
“Sprinklers are a tool that can certainly be helpful particularly when the temperatures outside are in the 85-95 F range,” Watkins said. For temperatures higher than 95 cool cells will be necessary.
